<!doctype html>
<html>
  <head>
    <title>Calculator</title>
  </head>
  <body>
    <form>
      <table border="1" cellpadding="0">
        <colgroup>
          <col width="20%" />
          <col width="20%" />
          <col width="20%" />
          <col width="20%" />
        </colgroup>
        <tbody>
          <tr align="right">
            <td colspan="4">
              <input type="text" name="result" id="result" size="40"/>
            </td>
          </tr>
          <tr align="center">
            <td>
              <input type="button" style="width: 50px;height: 50px" value="1" name="number1" id="number1"/>
            </td>
            <td>
              <input type="button" style="width: 50px;height: 50px" value="2" name="number2" id="number2"/>
            </td>
            <td>
              <input type="button" style="width: 50px;height: 50px" value="3" name="number3" id="number3"/>
            </td>
            <td>
              <input type="button" style="width: 50px;height: 50px" value="+" name="symbol+" id="symbol+"/>
            </td>
          </tr>
          <tr align="center">
            <td>
              <input type="button" style="width: 50px;height: 50px" value="4" name="number4" id="number4"/>
            </td>
            <td>
              <input type="button" style="width: 50px;height: 50px" value="5" name="number5" id="number5"/>
            </td>
            <td>
              <input type="button" style="width: 50px;height: 50px" value="6" name="number6" id="number6"/>
            </td>
            <td>
              <input type="button" style="width: 50px;height: 50px" value="-" name="symbol-" id="symbol-"/>
            </td>
          </tr>
          <tr align="center">
            <td>
              <input type="button" style="width: 50px;height: 50px" value="7" name="number7" id="number7"/>
            </td>
            <td>
              <input type="button" style="width: 50px;height: 50px" value="8" name="number8" id="number8"/>
            </td>
            <td>
              <input type="button" style="width: 50px;height: 50px" value="9" name="number9" id="number9"/>
            </td>
            <td>
              <input type="button" style="width: 50px;height: 50px" value="*" name="symbol*" id="symbol*"/>
            </td>
          </tr>
          <tr align="center">
            <td colspan="2">
              <input type="button" style="width: 100px;height: 50px" value="0" name="number0" id="number0"/>
            </td>
            <td>
              <input type="button" style="width: 50px;height: 50px" value="." name="symbol." id="symbol."/>
            </td>
            <td>
              <input type="button" style="width: 50px;height: 50px" value="/" name="symbol/" id="symbol/"/>
            </td>
          </tr>
        </tbody>
      </table>
    </form>
  </body>
</html>